Benzindole cyanotrimethine basic dyestuffs



United States Patent 3,399,191 BENZINDOLE CYANOTRIMETHINE BASIC DYESTUFFS Alfred Brack, Leverkusen, Germany, assignor to Farbenfabriken Bayer Aktiengesellschaft, Leverkusen, Germany, a corporation of Germany No Drawing. Filed June 23, 1964, Ser. No. 377,369 Claims priority, appliclgtiog 6Germany, Aug. 30, 1963,

O 8 Claims. ci.260-240.6

ABSTRACT OF THE DISCLOSURE Basic dyestuffs of the formula A t t, m in wherein R is lower alkyl, cycloalkyl, aralkyl, or aryl; Z is hydrogen or a nonionic substituent, n equals 1-2; R is hydrogen or cyano; R is hydrogen, phenyl, cyano, car-b0 lower alkoxy; A is the residual member of a ring which when included with The invention relates to valuable new dyestuffs; more particularly it relates to dyestuffs of the general formula These dyestuffs can he prepared, by a method known per se, by means of condensation or quaternisation. The symbols in Formula I denote: R an alkyl, cycloalkyl, aralkyl or aryl radical, R hydrogen, an alkyl, cycloalkyl, aralkyl, or aryl radical or a nonionic derivative of the carboxyl group, such as the nitrile, carboxylic acid ester or ca-rboxylic acid amide group, R hydrogen, an aryl radical, a nitrile, carboxylic acid ester or carboxylic acid amide group, R an alkyl, cycloalkyl, aralkyl or aryl radical, A the residual parts of an unsaturated heterocyclic 5- or 6-membered ring, to which other rings may be condensed, and X an anion. The aromatic rings and the radicals R, R R R and/or A may contain nonionic substituents, but shall be free of sulfonic acid and car-boxylic acid groups.

The dyestuffs (I) are obtained when compounds of the general formula or their functional derivatives are condensed with compounds of the general formula AN mating) 1 1; (III) or their salts of the formula A [R2 -CHZ O w X- B3 (IIIa) or when compounds of the formula R1]T(|3=CI-IR1 @k/ (IV) or their salts of the formula R'1TI:(|JCI'I2R1 (:O XH

(IVa) are condensed with compounds of the formula or their functional derivatives; functional derivatives of the aldehydes II or V are such compounds in which the CH0 group is replaced by a functionally equivalent group, e.g., by the azomethine, acetal or nitron group. Functional derivatives which are particularly accessible and suitable are the salt-like primary products of the Vilsrneier aldehyde synthesis. In the Formulae II, III, IIIa, IV, 'IVa and V, R, R R R and A have the above specified significance, the radicals X represent anions and the aromatic rings as well as R, R R R and A may contain nonionic substituents.

In accordance with another method of preparation, the novel dyestuffs may be synthesised by treating a dyestuif base of the general formula 3 with quaternising reagents. The starting dyestuffs (VI) employed for this purpose may for instance be prepared by condensing a compound (H) or one of its functional derivatives with a compound of the formula (VII) R R1 Y Y1 Y2 Methyl Hydrogen... Hydrogen.-. Hydrogen Hydrogen.

D Cyauo do "do Do. Do Hydrogen. Bromine do Do.

Do .do Hydrogen do, Drmethylammo. Do do do do Methoxy.

..do. Hydrogen Bromine do Do. do...- Bromine Do. Chlorine Chlorine. Do Hydrogen. Hydrogen Do. .do do-.. Do. do Do. do Do. do Do. do. Do. Phenyl o do do D0. -ethoxyphenyl "do do do D0. Methyl do do t. Ethyl Do.

These are available, in the form of their salts of Formula Na, in accordance with the process of U.S. patent application Ser. No. 356,979. Suitable compounds of Formula II are obtained from these compounds by the introduction of an aldehyde group according to the usual methods, e.g., according to the Vilsmeier process.

Suitable compounds of Formula III and IIIa are for example:

1,3,3-trimethyl-2-methylene-dihydro- 2,3 -indole, 1,3,3-trimethyl-Z-cyanomethylene-dihydro- (2,3 -indole, 1,3,3-trimethyl-2- (N-ethyl) -carboxylamidomethylenedihydro- 2,3 -indole, 1,3, 3-trimethyl-Z-cyanomethylene-S-methoxy-dihydro- (2,3 -indole, 1,3,3-trimethyl-2-cyanomethylene-S-ethoxy-dihydro- (2,3 -indole, l,3,3-trimet'hyl-2-cyanomethylene-S-chloro-dihydro- (2,3

indole, 1,3,3-trimethyl-2-cyanomethylene-S-bromo-dihydro- (2,3

indole, 1,3,3-trimethyl-2-cyanomethylene-S-methyl-dihydro- (2,3 -indole, 1,3,3-trimethyl-2-cyanomethylene-S-isopropyl-dihydro- (2,3 )-indole, 1,3,3-trimethyl-2-cyanomethylene-S-carboxymethyldihydro- (2,3 )-indole, 1,3,3-trimethyl-2-cyanomet'hylene-S-acetamino-dihydro- (2,3 -indole, 1,3 ,3-trimethyl-2-cyanomethylene-S-methylsulphonylamino-dihydro- (2,3 -indole,

4 1,3,3-trimethyl-2-cyanomethylene-7-ethyl-dihydro- (2,3

indole, 1,3,3-trimethyl-2-cyanomethylene-7-methoxy-dihydro- (2,3 )-indole, 1,3,3-trimethyl-2-cyanomethylene-7-chloro-dihydro- 2,3 -indole, 1,3,3-trimethyl-2-cyanomethylene-5-methoxy-7-chloro dihydro- (2,3 -indole, 1-ethyl-3,3-dimethyl-Z-cyanomethylene-dihydro-(2,3

indole, 1-benzyl-3,3-dimethyl-2-cyanomethylene-S-methoxydihydro- (2,3 -indole, 2,3-dimethyl-benzthiazolium methosulphate, 2-cyanomethyl-3-methyl-benzthiazolium chloride,

bromide, iodide and methosulphate, 2-cyanomethyl-3-ethyl-benzthiazolium p-toluenesulphonate, l,3-dimethyl-Z-cyanomethyl-benzimidazolium chloride, 1-isobutyl-2-cyanomethyl-3-ethyl-benzimidazolium ethyl-sulphate, 1-phenyl-2-cyanomethyl-3-ethyl-benzimidazolium iodide, l,3-dimethyl-2-benzyl-benzimidazolium methosulphate, 1,3 6-trimethyl-4-methylene-dihydro (3 ,4)

pyrimidone (2 1,4-dimethyl-Z-methylene-dihydro(1,2)-quinoxalone-(3), 1,2- and 1,4-dimethyl-pyridiniu1n methosulphate, 1,2- and 1,4-dimethyl-quinolinium methosulphate and 1-methyl-4-cyanomethyl-quinolinium methosulphate.

It again is possible to introduce an aldehyde group into these compounds, at the CH- or CH group of the compounds of Formulae III or IIIa by the normal methods, for instance according to Vilsmeier, so as to form products of Formula V.

Suitable compounds of the general Formula VII are for instance 2,3,3-trimethyl-indolenine, 2cyanomethyl- 'benzimidazole, 1-methyl-2-cyanomethyl-benzimidazole, 1- methyl-benzimidaz0le-2-acetic acid methyl, or ethyl or isobutyl-ester, l-methyl-Z-benzyl-benzimidazole, l-phenyl- 2-methyl-benzimidazole, 2-cyanomethyl-benzoxazole, 2- cyanomethyl-benzthiazole, 2-cyanomethyl-perimidin CH CN NII and 1-phenyl-2-cyanomethyl-triazole-( 1,3,4).

Condensation of the various starting components for the production of the novel dyestuffs (I) is carried out by treating the components with water-eliminating agents at temperatures between 25 and 150 C., preferably between 50 C. and C. For this purpose, it is an advantage to employ an inert liquid and/or an excess of the condensation reagent as the solvent or diluent. Suitable condensation reagents are, for instance, inorganic and organic acids, such as hydrochloric acid, phosphoric acid, polyphosphoric acid, formic acid, acetic acid, propionic acid and chloroacetic acid, acid anhydrides such as acetic anhydride, acid chlorides such as phosphorus oxychloride, phosphorus trichloride, thionyl chloride, sulphuryl chloride and phosegene, as well as mixtures of these reagents.

Suitable solvents or diluents are, for instance, ethylene chloride, chloroform, carbon tetrachloride, acetylene tetrachloride, benzene, chloroand dichloro-benzene, ni-trobenzene and dioxane, etc.

-It has to be understood that the type of the anion X usual in basic dyestuffs does not affect the dyeing properties of the novel dyestuffs. From their preparation the dyestuffs will normally exhibit anions like halide anions, in particular Cland/or Br", or sulfonate groups, such as OSO CH or 0SO C H or p-toluene sulfonate;

in general, the nature of the anion depends on the mode of production, purification and/or precipitation of the dyestufi. The anion can, however, be replaced by other anions normally encountered in dyestuif salts of basic dyestuffs by methods known as such; for this purpose the dyestuff salt is first converted into the free base by neutralizing it with a basic reagent, such as sodium carbonate, sodium hydroxide and the like, and when this base is then converted into the form of the desired salt with the corresponding organic or inorganic acid by means of this procedure, it is possible to obtain dyestuif salts which contain, for example, [BF benzene sulfonate, phosphate, acetate, chloro zincate, perchlorate, N sulfate, oxalate, formate, citrate, maleinate, tartrate, benzoate, lactate, propionate, butyrate or succinate radicals as the anions.

The dyestuffs to be obtained according to the invention are novel. They are suitable for dyeing and printing on synthetic, semisynthetic and natural fibre materials, such as polymers and copolymers of acrylonitrile and of asymmetrical dicyanoethylene, cellulose esters, silk and mordant cotton. In addition, they can serve for the production of liquid inks and pastes for ball point pens, and for dyeing paper, coconut fibre or jute and for the colouring of gum printing pastes.

The novel dyestuffs give very good yields and are characterized by a very good absorption capacity with a very good levelling capacity. They do not dye the woolen fraction in mixed fibres of fabrics. Dyeing and printings on materials which consist wholly or predominantly of polymers and/or copolymers of acrylonitrile and/or asymmetrical dicyanoethylene are characterized by their extraordinary brilliance and excellent fastness properties, particularly by very good fastness to light, wetting, hotpressing, abrasion and sublimation.

The following examples are given for the purpose of illustrating the invention. The parts specified therein are parts by weight.

EXAMPLE 1 5.6 parts of the compound and 5.0 parts of 1,3,3-trimethyl-Z-cyanomethylene-dihydro-(2,3)-indole are heated to 50 C. with 50-100 parts of chloroform, whilst stirring. The mixture is then treated dropwise with 5-10 parts of phosphorus oxychloride and thereafter boiled for another 20-30 minutes. The chloroform is subsequently distilled ofi, preferably under a somewhat reduced pressure, and the residual dyestuif recrystallised from 500 parts of Water at about 90 C. The dyestuif of the formula is obtained in a vary good yield, and dyes polyacrylonitrile fibres a blue shade with very good fastness properties.

6 EXAMPLE 2 23.2 parts of the compound one of the following compounds is used valuable colouristically similar dyestuffs are likewise obtained by the same procedure.

5.7 parts of 1,3,3-trimethyl-2-cyanomethylene-S-methoxydihydro-(2,3)-indole are heated at -80 C. for 1 hour with -100 parts of ethylene chloride and 7-10 parts of phosphorus oxychloride, whilst stirring. The excess of phosphorus oxychloride is thereafter destroyed by the addition of water and the ethylene chloride is removed by steam distillation. The dyestuif of the formula CH3 Clix-- N ha.

partly separates from the remaining aqueous solution on cooling. The separation is completed by the addition of a saturated solution of sodium chloride. The resultant dyestuff dyes polyacrylonitrile fibres and fabrics a brilliant blue shade with excellent fastness properties, especially very good fastness to light, to rubbing, to sublimation, to wet processing and to decatizing.

When the above-mentioned aldehyde is replaced by the compound of the formula (melting point l60-163 C.), the dyestutf of the formula is obtained by the same procedure, and this dyes polyacrylonitrile materials to brilliant greenish blue shades with excellent fastness properties.

EXAMPLE 4 42 parts of 1,3,3-trimethyl-2-methylene-S-arnino-dihydro-(2,3)-indole are heated at 7080 C. for 1 hour with 150 parts of glacial acetic acid and 90-100 parts of acetic anhydride. The mixture is then treated with 52 parts of the compound CH3 C H NHC CH3 and it dyes polyacrylonitrile fibres and fabrics deep blue shades.

The employed aldehyde was prepared as follows:

100 parts of a 6% aqueous solution of cyanogen chloride are placed over a layer of 200 parts of chloroform. 12 parts of the compound are added first of all, a solution of 8.5 parts of sodium hydrogen carbonate in 100 parts of water is then added dropwise to it at room temperature, whilst stirring, and stirring of the mixture is continued at room temperature for several hours or overnight. On evaporation, the sep arated chloroform phase leaves the compound of the formula C3H5III(IJ=CH-CN as the residue in an almost quantitative yield, this being obtained at a degree of purity good enough for further processing.

After recrystallisation from methyl-cyclohexane, its melting point is 127 C.

6.6 parts of the residue from the chloroform phase are dissolved in 20 parts of dimethylformamide, whilst heating. 6 parts of phosphorus oxychloride are added dropwise to this solution at 5060 C. Whilst stirring well, and it is kept at this temperature for another 2 hours. When the reaction mixture is poured into 100200 parts of water, an orange coloured solution is obtained, and the aldehyde of the formula separates from this solution in a pure state when about 20 parts of concentrated sodium hydroxide solution are added. Its melting point is 176-180 C.

EXAMPLE 5 24.8 parts of the aldehyde employed in Example 4 and 19 parts of 1,4-dimethyl-2-methylene-dihydro-(1,2)-quinoxalone-(3) are heated to boiling for 2 hours with 200- 300 par-ts of carbon tetrachloride and 20 parts of phosphorus oxychloride. The separated dyestutf is recrystallised from dilute acetic acid. Its composition corresponds to the formula and it gives fast blue-green dyeings on polyacrylonitrile.

When the above-mentioned quinoxalone is replaced by the equivalent amount of 1-methyl-4-n-propyl-, l-methyl- 4-benzyl-, 1-methyl-4-fl-phenylethyl-, l-methyl-4-cyclohexylor l-methy1-4-phenyl-2-methylene-dihydro-(1,2)- quinoxalone-(3), very similar dyestuffs are obtained by the same procedure.

EXAMPLE 6 24.8 parts of the aldehyde employed in Example 4 and 14 parts of 1,3,6-trimethyl-4-methylene-dihydro-(3,4)- pyrimidone-(Z) are heated at 100-105 C. for 3-4 hours with parts of glacial acetic acid and 20 parts of acetic anhydride. The cooled dyestuff solution is then. poured into about 1000 parts of a 5-l0% solution of sodium chloride, when the dyestuif of the formula is precipitated. It is suitable for dyeing and printing on acetate silk, giving blue shades.

9 EXAMPLE 7 22.3 parts of 'the aldehyde employed in Example 1 are heated at 95105 C. for 3 hours with 17.5 parts of 1,3,3- trimethyl-2-methylene-dihydro-(2,3)-indole and a mixture of 50 parts of acetic acid, 50 parts of propionic acid and parts of concentrated hydrochloric acid. When the cooled condensation mixture is poured into a dilute aqueous solution of sodium chloride, the dyestutf of the formula separates, and this dyes polyacrylonitrile or acetate silk materials very clear, strongly greenish blue shades.

This dyestutf is also obtained when the abovementioned starting compounds are replaced by 23.2 parts of the compound and 20.1 parts of l,3,3-trimethyl-2-methylene-dihydro- (2,3 )-indole-w-aldehyde during the identical procedure.

EXAMPLE 8 is obtained, and this dyes polyacrylonitrile fibres blue shades with very good fastness properties.

When the above mentioned aldehyde is replaced by the use of an equivalent amount of 5-methyl-, 5-methoxy-, 5-ethoxy-, 5-chloro-, 5-bromo-, 5-carbomethoxy-, 7-chloro-, 7-ethylor 7-methoxy-1,3,3-trimethyl-2-methylene-dihydro-(2,3)-indole-w-aldehyde, dyestuffs with similar coloristic properties are obtained by the same procedure.

EXAMPLE 9 8.6 parts of l-methyl-Z-cyanomethyl-benzimidazole and 11.1 parts of the aldehyde employed in Example 1 are stirred With 100 parts of ethylene chloride. When 17 parts of phosphorus oxychloride are added, the temperature quickly rises to about 60 C.; it is further heated to the boil, the mixture is kept under reflux for 2-3 hours and the ethylene chloride is then distilled off. The residue,

10 which is only little soluble in alcohol, is extracted by boiling with 200 parts of alcohol and thereafter stirred at room temperature for several hours with excess of a 20% solution of sodium carbonate. The resultant product largely consists of the compound of the formula and melts at 200-204 C.

5 parts of this crude product are dissolved in about 500 parts of toluene and heated to boiling for 1-2 hours with 2 parts of dimethyl sulphate which is free from acid. The dyestuff of the formula separates. It dyes polyacrylonitrile fibres and fabrics violet shades with very good fastness properties.

When the 1-methyl-2-cyanomethyl-benzimidazole is replaced by the equivalent amount of 1-ethyl-, 1-n.propyl-, l-isobutylor 1-phenyl-2-cyanomethyl-benzimidazole, dyestuffs with similar coloristic properties are obtained by the same procedure.

EXAMPLE 10 24.5 parts of the compound and 20.1 to 20.5 parts of l,3,3-trimethyl-2-methylenedihydro-(2,3)-indole-w-aldehyde are stirred for two hours in a boiling water bath with 200 arts of glacial acetic acid and 30-50 parts of acetic anhydride.

The deep blue solution is poured into ten times its volume of water and the dyestuff of the formula is isolated as usual. It dyes polyacrylonitrile, acetate silk or tanned cotton materials to greenish blue shades.

When the above-mentioned aldehyde is replaced by the equivalent amount of 5-methyl-, 5-ethyl-, 5-methoxy-, S-ethoxyor 5-bromo-1,3,3-trimethyl-2-methylene-dihydro-(2,3)-indole-w-aldehyde, similar dyestufis are obtained by the same procedure.

EXAMPLE 11 The amount of polyacrylonitrile fibres corresponding to a goods-to-liquor ratio of 1:40 are introduced at 40 50 C. into an aqueous dye liquor which contains per 11 litre 0.75 g. of 30% acetic acid, 0.40 g. of sodium acetate, and 0.20 g. of the dyestutf of the formula the bath is heated to boiling during about 30 minutes whilst the fibre material is moved about in it, and it is maintained at the boiling point for 30 minutes to one hour. After the fibres have been rinsed and dried, a very clear blue dyeing results with excellent fastness properties.

EXAMPLE 12 A polyacrylonitrile fabric is printed with a paste of the following composition: 30 parts of the dyestutf prepared according to Example 1, 50 parts of thiodiethylene glycol, 30 parts of cyclohexanol, 30 parts of 30% acetic acid, 500 parts of crystal gum, 30 parts of aqueous zinc nitrate solution (d=1.5) and 330 parts of Water.

After drying, the print is steamed for 30 minutes and thereafter rinsed. A very fast blue print is obtained.

I claim:

1. A dyestuff of the formula:

wherein R stands for a member selected from the class consisting of lower alkyl, cy-clohexyl, phenyl, phenyl lower alkyl, lower alkoxy phenyl; Z stands for a member selected from the class consisting of hydrogen, bromine, chlorine, methyl, ethyl, methoxy, ethoxy, dimethylamino; n stands for an integer ranging from 1 to 2 when Z is bromine or chlorine and for the integer 1 when Z is other than bromine or chlorine; R stands for a member selected from the group consisting of hydrogen and -CN; R stands for a member selected from the class consisting of hydrogen, phenyl, -CN and carbo lower alkoxy, with the proviso that at least one of R and R is --CN; A stands for the residual member of the ring including taken from the class consisting of dihydro-indole, benzthiazole, benzimidazole, dihydropyrimidone, dihydroquinoxalone, pyridine, quinoline, benzoxazole, and triazole; R is a member selected from the group consisting of alkyl, cycloalkyl, phenyl, and benzyl; and X is an anion used for the salt formation of basic dyestuffs; the dyestulf being free of sulfonic acid and carboxylic acid groups.

2. The dyestufi of the formula CH7, CH1

12 3. The dyestutf of the formula CH3 on, 1 m

, c1 0 H5or-1 =o--c11=onc N 4. The dyestutf of the formula CH: 011; l C. H5CrN=CC=CH-OH I (IN N 5. The dyestuff of the formula on, 1 H: Cl

H50,-N==cc=oH-(JH I (IN N i OH; K/

6. The dyestutf of the formula 1 on. 1 cm 0 H C -I\|I=C-C=CHOH- N 7. The dyestutf of the formula on, 00,11, c1

H5o,-N= 3--o=Gn-oH 8. The dyestufi of the formula o1 H C;1II=C-C=CH-CH N N $113 References Cited UNITED STATES PATENTS 2,310,640 2/1943 Kendall 260-24065 XR 2,610,121 9/1952 De Smet et al. 260-2406 XR 3,320,279 5/ 1967 Brack 260240 FOREIGN PATENTS 897,197 5/1962 Great Britain.

OTHER REFERENCES Ficken et al.: J. Chem. Soc., 1960, pp. 1537-1541. Chemical Abstracts, vol. 54, col. 24795 (1960).

JOHN D. RANDOLPH, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,399,191 August 27, 1968 Alfred Brack It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, lines 46 to 54, the right-hand portion of the formula should appear as shown below:

same column 1, line 54, to the right of the formula insert (I) Column 2, lines 11 to 17, the portion of the formula reading II should read I Column 4, line 65, "phosegene" should read phosgene Column 5, line 74, "vary" should read very Column 12,

lines 2 to'l0, the left-hand portion of the formula should appear as shown below:

Signed and sealed this 10th day of February 1970.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents 

